S-Block series

The Sprenger S-Block series is available in three different bearing configurations:

• Plain bearings: Identifiable by the yellow dot on the reinforcement tab.
  
• Ball bearings: Marked with a red dot on the reinforcement tab.
  
• Needle roller bearings: Identified by a blue dot on the reinforcement tab.
  

This makes it possible to see at a glance which type of bearing is fitted in each block.

Absolutely not! Standard pulleys are usually fitted with plastic sheaves designed for use with rope.

The steel wires contained in wire ropes place significantly greater demands on the material of the sheave. Plastic sheaves cannot withstand this stress and would be damaged. Therefore, only pulleys specifically designed for wire ropes should be used.

Ball bearing blocks are characterised by their exceptionally smooth running and are therefore ideal for applications where lines need to be pulled through quickly and effortlessly by hand.

Typical applications include, for example, single-line reefing systems, redirecting sheets, or hauling in and letting out the traveller. Thanks to their low-friction operation, lines can be trimmed with particular precision, which offers a significant advantage, especially in light winds.

On small boats, where most lines are operated by hand, the use of ball-bearing blocks is therefore particularly advantageous.

Needle roller bearings, also known as roller bearings, are among the highest-performance bearings for high-quality, heavy-duty blocks. Compared to ball bearings, they have significantly larger contact surfaces, which enables them to withstand higher loads whilst ensuring smooth, ‘rolling’ operation.

Thanks to these properties, needle roller bearings combine the advantages of plain bearings and ball bearings: they are particularly robust, like plain bearings, whilst also running smoothly, like ball bearings.

Needle roller bearing blocks are therefore primarily used in applications involving very high working loads, where maximum load-bearing capacity and reliable operation are crucial.

In plain bearing blocks, the disc runs directly on a shaft without any additional ball or roller bearings. The disc is usually made of nylon or other materials that offer good sliding properties and are durable.

Provided high-quality materials are used and the shaft has the largest possible diameter, these comparatively simple blocks are very robust, durable and maintenance-free. They also ensure smooth running.

Plain bearing blocks are particularly suitable for applications involving static or continuously applied loads.